21072500473 has 2 divisors, whose sum is σ = 21072500474. Its totient is φ = 21072500472.

The previous prime is 21072500437. The next prime is 21072500483. The reversal of 21072500473 is 37400527012.

Together with previous prime (21072500437) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15875244009 + 5197256464 = 125997^2 + 72092^2 .

It is a cyclic number.

It is not a de Polignac number, because 21072500473 - 2¹⁷ = 21072369401 is a prime.

It is not a weakly prime, because it can be changed into another prime (21072500413) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10536250236 + 10536250237.

It is an arithmetic number, because the mean of its divisors is an integer number (10536250237).

Almost surely, 2^21072500473 is an apocalyptic number.

It is an amenable number.

21072500473 is a deficient number, since it is larger than the sum of its proper divisors (1).

21072500473 is an equidigital number, since it uses as much as digits as its factorization.

21072500473 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 11760, while the sum is 31.

The spelling of 21072500473 in words is "twenty-one billion, seventy-two million, five hundred thousand, four hundred seventy-three".